SAN FRANCISCO (KCBS) – Federal fish and wildlife authorities are trying to figure out whether Port of San Francisco workers violated federal law when they destroyed a birds’ nest on a crane near Pier 80, where Oracle’s America’s Cup yacht-racing team has set up shop.

It was not just any birds’ nest; it was home to a pair of rare ospreys, which were once near extinction. They had never been seen before in San Francisco, until the nest appeared on the crane last summer.

The ospreys had been away for the winter and just last week, port workers smashed their nest. Now, federal investigators are looking into whether that might have violated the Migratory Bird Treaty Act, a federal law that makes it illegal to destroy with an “active” raptor’s nest during mating season.

Last year, the port agreed to shut down the crane to allow the birds to nest. But they were only willing to wait so long, as the crane unloads ship cargo and is also used to lift Oracle America’s Cup boats in and out of the water.

So after about six months, port workers took steps to discourage the birds from returning – they put reflectors and wires on the crane and even built a device that makes a sound to annoy the birds.

Potrero Hill naturalist Eddie Bartley spotted an osprey flying in the area recently and was convinced it was one of the two that had nested on the crane last year. But his excitement was short-lived as the next day, he saw two ospreys flying away from Pier 80. It was at that point when he saw port workers destroy the nest.

Officials with the U.S. Department of Fish and Wildlife said they are “looking into” the matter.

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